Children around the world face difficult situations such as poverty, hunger, illiteracy, health problems, and lack of basic sanitation. Poverty is common in poorer countries and is caused by lack of resources and unequal income distribution. Hunger is caused by poverty where people cannot afford food or water, and leads to malnutrition. Illiteracy, the inability to read or write, affects nine out of ten people in non-Christian parts of the world and is increasing in some countries without basic education. Health problems like heart disease and infections are found worldwide. Lack of basic sanitation, including toilets, is caused by poverty and means people must consume their own waste.